Way out in space, far beyond the reaches of our own small galaxy, a brief shudder of heat has signaled the death of a planet–and in quite spectacular fashion. It seems to have been swallowed by its own sun. A joint Spanish-Polish-American team working with the Hobby Eberly telescope in Jeff Davis County, Texas became the first humans to find evidence of a planet being swallowed by a neighboring star, when they noticed last week the red giant BD+48 740 was burning hotter, and burning lithium. Astronomical theorists, as it turns out, have determined but a very few instances in which lithium can be found in stars, and one of them is if a star were to swallow a too-cozy world. Additional evidence comes from the almost comically elliptical orbit of another body moving around BD+48 740, whose bizarre trajectory hints at the recent disappearance of another, similar body from orbit.
This situation, while astonishingly rare on human time, is in fact the fate of all planets. As a star grows old (say 2 billion years) it begins to exhaust the hydrogen fuel at its center, crumbling slowly on itself before the pressure of the collapse incites new fusion. The star then burns red and brighter than before, expanding in an effort to let heat escape from its core (and swallowing any poor planets in the way) before collapsing in on itself again and becoming either an ultra-dense white dwarf, a brightly shattered nebulae or a fathomless, lightless black hole. The same thing will happen to earth, when the sun becomes a red giant (as it surely will) and expands. Two bright spots (forgive the pun, if in fact it is one). In the first place, heat or UV rays from the expanding ball of nuclear fusion would kill us long before we were actually swallowed up. And two, this event is not likely to happen for another 5 billion years. So keep eating those vegetables. // Patrick Barrett
